Commercially available high current ion sources are based on microwave plasma generation, typically powered by a magnetron. They have demonstrated very high currents (>100 mA D+) and high current density (>350 mA/cm2). Most commercial available plasma sources are based on an electron cyclotron resonance (ECR) process to increase the ion density in a plasma. The ECR process requires high magnetic fields and hence large magnets. While they are able to reach high current density and high ion current, they consume a lot of power (kW) and are not power efficient. They also have large footprint (volume and “linear” dimensions) and heavy weight due to the associated components, such as microwave power supplies, matching networks and magnets. They often require significant thermal management and liquid cooling. Efforts to reduce the size of these types of RF ion source have focused on operating the microwave plasma devices in the inductively coupled mode to increase the atomic ion fraction in the plasma. By reducing the power required, the size of the power supply could be reduced. However, a microwave power supply fundamentally still requires huge infrastructure, and there is still a huge power, size and weight overhead for generating ions. Hence, they are not viable options as portable ion sources.